Agar and Carrageenan Think about the chemical structure of carrageenan and agar - what do they have in common?
Agar = Ø Extracted from seaweed and is used in many foods as a gelling agent. Ø Agar is a polymer of agarobiose, a disaccharide composed of D-galactose and 3,6-anhydro-L-galactose. Ø Highly refined agar is used as a medium for culturing bacteria, cellular tissues, and for DNA fingerprinting. Ø used as = An ingredient in desserts in Japan and other Asian countries. The gels produced with agar have a crispier texture than the desserts made with animal gelatin.
Carrageenan = Ø A generic term for several polysaccharides also extracted from seaweed. Ø Carrageenan compounds differ from agar in that they have sulfate groups (-OSO3-) in place of some hydroxyl groups. Ø used as = Thickening, suspending, and gelling food products.
Carrageenan consists chiefly of potassium,sodium,calcium,magnesium,and ammonium sulfate esters of galactose and 3,6-anhydrogalactose copolymers. These hexoses are alternately linkeda-1,3andb-1,4in the polymer.The prevalent copolymers in the hydrocolloid are designatedkappa-,iota-,andlambda-carrageenan.
Agar and Carrageenan
Think about the chemical structure of carrageenan and agar - what do they have in common?
Agar =
Ø Extracted from seaweed and is used in many foods as a gelling agent.
Ø Agar is a polymer of agarobiose, a disaccharide composed of D-galactose and 3,6-anhydro-L-galactose.
Ø Highly refined agar is used as a medium for culturing bacteria, cellular tissues, and for DNA fingerprinting.
Ø used as =
An ingredient in desserts in Japan and other Asian countries. The gels produced with agar have a crispier texture than the desserts made with animal gelatin.
Carrageenan =
Ø A generic term for several polysaccharides also extracted from seaweed.
Ø Carrageenan compounds differ from agar in that they have sulfate groups (-OSO3-) in place of some hydroxyl groups.
Ø used as =
Thickening, suspending, and gelling food products.
Carrageenan consists chiefly of potassium,sodium,calcium,magnesium,and ammonium sulfate esters of galactose and 3,6-anhydrogalactose copolymers.
These hexoses are alternately linked a-1,3and b-1,4in the polymer.The prevalent copolymers in the hydrocolloid are designated kappa-,iota-,and lambda-carrageenan.